If the world is in a new era, ready to fight against climate change, as President Obama says, how come the road he charted looks as long and arduous as ever?

"As we head towards Copenhagen [Denmark, scene of key climate talks in December], there should be no illusions that the hardest part of our journey is in front of us," Mr. Obama said in a speech to the United Nations Tuesday. "Every nation's most immediate priority is reviving their economy and putting their people back to work. And so all of us will face doubts and difficulties in our own capitals as we try to reach a lasting solution to the climate challenge."

The president knows that only too well. There's such strong congressional opposition to caps on greenhouse gases that he's left in an awkward position. He wants to move forward on an international agreement but can't promise that the US will make the emissions cuts that any agreement might call for.

The sticking point, of course, is industry. No nation wants to burden its companies with costly regulations or fees that put them at a disadvantage to their competitors in other nations . The trick, Obama said, would be to get all the major emitters to agree on a framework. But developed nations want developing nations (read: China) to curb the big emissions boosts that their industrialization holds in store; developing nations want financial help, fearing the curbs will slow their growth too much.

The lingering effects of the "great recession" are complicated the process, Obama acknowledged in his speech. "The good news is that ... there's finally widespread recognition of the urgency of the challenge before us. We know what needs to be done," he added. "It's a journey that will require each of us to persevere through setbacks and fight for every inch of progress, even if it comes in fits and starts. So let us begin."
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